Thanks again EG. Apparently it's doable but difficult, that's why he's asking for the BCD and bore. I guess the machine is easier to setup with those numbers rather than working out the BCD from the bolt to bolt data.

I'm having him send what he has as I am confident that we are all on the same page and I can use what he's made for you.

I appreciate your help EG. Michael of LightningRods has been excellent to work with. Most of my parts are in now and I have the Big Block and sprocket coming. My little BOMA is working a bit too hard on my hills.

E-ScooterDude wrote:Thanks again EG. Apparently it's doable but difficult, that's why he's asking for the BCD and bore. I guess the machine is easier to setup with those numbers rather than working out the BCD from the bolt to bolt data.

I'm having him send what he has as I am confident that we are all on the same page and I can use what he's made for you.

I appreciate your help EG. Michael of LightningRods has been excellent to work with. Most of my parts are in now and I have the Big Block and sprocket coming. My little BOMA is working a bit too hard on my hills.

What he made for me was a perfect fit. He sent me a PDF with the hole pattern. I printed it and then sat it on top of the hub. It matched up perfectly so I told him to make it. He may have forgotten about that file. It's been a good while.

First off solid props to shortcircuit911 for modding these front forks and making the steering tube a bit longer for me. The original front forks had no shocks and are too narrow for a disk brake and had no good way to mount a caliper to them These forks had everything except the down tube was about an inch too short so he lengthened it for me.

I was concerned that the shaft to bell union was not going to hold and sure enough, two little set screws on two flats on the shaft were not enough. I suppose if the motor was turning lots of RPM's and then geared down a good bit, then they would have been enough, but my motor is direct to the back wheel so it will see a good bit of torque on the shaft. I had already cut the original shaft off too short to add anything to it, so I bought more shaft and cut it a bit longer. The new shaft is much harder than the original one. Cutting it on my band saw took 20 minutes. I could not drill it with HSS bits at all. Fortunately I have carbide end mills that cut the hardened steel easily enough. This is the end of the prop adapter that came with the motor. It uses 4 screws to bolt to the top of the bell. I drilled 4 holes through it for set screws. One set of holes are threaded straight through so a single set screw goes right through the shaft. The other two set screws just sit on flats on the shaft. The bell also has two set screws in it that sit on flats on the shaft. That ought to do the job.

I have 3 20S LIPO packs that I pulled from the blue scooter a while back. They had several bad cells in them. I finally got around to taking the packs apart and discarded the bad cells. I then made another 12S pack that went in the Currie. The two packs have their own individual BMS. The green pack is 10,000mah and the rebuilt pack is 8000mah.

The Grinfineon controller is a perfect fit under the back deck. It currently has IRF4110 mosfets in it. I'll replace them with AOT290's once they arrive. They will increase the controllers wattage by another 50% and have much less Rds so the controller will not only run at higher wattage, but run cooler too. This isn't the final controller for the scooter. I have a Power Velocity controller coming that will get AOT290's as well. It's will be added later. Obviously I need to bind up the phase and power wires a bit, but that's a couple of zip ties. Under the motor are two IP68 connectors. One is the throttle and controller enable signals and the other is for the rear lights. Power to the controller is two 10 awg wires with 5.5mm bullets.

Last edited by ElectricGod on Aug 28 2017 6:17pm, edited 1 time in total.

My Power Velocity 12 fet controller arrived today. It's 1/2" shorter than the Grintech. I'll swap out the power and phase wires for 10 or 12 awg silicon. I read on another thread that people are putting IRF3077 mosfets in this controller and supposedly getting 4200 watts out of it. I'm seriously skeptical of those numbers on the IRF3077 since they are 370 watt fets. I'm going to use the AOT290. They are on order and are rated for 500 watts so getting 4000 watts in a 12 fet controller will be doable. Can't wait! The IRF3077 has a bit less Rds 2.8 micro ohms compared to the AOT290 at 3.5 micro ohms, but the IRF3077 is nearly 2X slower than the AOT290. The 3077 at 10 volts can handle more current 210 amps compared to 140 amps, but running them at 48 to 80 volts and that current difference wont matter anymore while the wattage will. At 370 watts and 82 volts, the IRF3077 can handle 4.5 amps. The AOT290 at 500 watts and 82 volts can handle 6.1 amps. I'm going to smoke the IRF3077 and keep pulling power on the AOT290. 4000 watts in a 6" long controller...damn!

Last edited by ElectricGod on Aug 28 2017 6:18pm, edited 1 time in total.

A few days ago the new forks arrived. I got around to taking off the old ones and installing the new ones. But first a few pics of them for comparison. The new ones are an inch longer in the forks and the down tube is about 2" longer. The new forks are about 3/4" wider too...making room to fit the disk brake. It's hard to see in the picture, but shortcircuit911 welded about a 3" long section in the middle of the down tube. TIG welding is the bomb! Anyway, the modified new forks were a perfect replacement for the old ones and I got another 2" of height on the handlebars to boot.

This is a small piece of flat steel. It's about 1.5" long. 6061 aluminum, would have worked, but this was a scrap off of something else that was already cut to the length I needed so I just used it. I'll probably take it off and shape it some more later, but it's a perfect fit to pull the top of the caliper out from the fork and allow the bottom bolt hole on the caliper to bolt in directly to the flange welded onto the forks. The adapter is bare steel, I'll need to clean it up some more and then paint it so it doesn't eventually rust. I've used some of this same steel on my blue scooter to reinforce the front folding section. It's been in place for at least 6 months and shows no evidence of rust so maybe I don't care too much. The top hole on the flange is elongated so I can slide the brake in or out a little, but this is dead center in the brake pads. I probably didn't need to do it, but I added a nylon nut to the M6 bolt in the flange. If there is a bolt that could interfere with the brake rotor, it would be this one. I would not want to find myself stopping suddenly when that bolt caught in the brake rotor and I go flying over the handlebars. The adapter is threaded and the bolt has locktite on it, it's already unlikely to ever come loose, but now it's virtually impossible.

and the old adapter that came with the caliper...like anybody cares.

The fit is pretty tight and there is almost no room between the rotor and the flange. The bottom bolt is 8mm. I tapped M8 threads into the bottom hole in the flange and then used some locktite on the threads. It ought to stay put. The top bolt is M6. This brake is not going anywhere. You can't see it in the pictures, but the piece of steel was the exact width needed to just kiss the inside of the rotor with the inner brake pad. The 8mm bolt needed a couple of shims. I used 2 washers and a nut to get it just right. Also, the width of the axle is 1/32 too narrow for the forks so I added a shim washer on the axle opposite side from the rotor. It's all a perfect fit. Almost like someone had a clue what they were doing! The rotor just skims the surface of the inner brake pad. When I squeeze the lever on the brake caliper it locks up nicely with no flexing or distortion of the rotor.

This scooter has seen so many changes to it since it got ridden last...some 6 months ago. Tonight is the first time it has been on two wheels since a long time ago.

I have 3 things left to do before I can ride it. I'm SOOOOOO close!!!
1. The front brake cable is too short. I think I have a longer one somewhere...so that will need to be replaced.
2. My thumb throttle is DOA. I have more linear halls so I need to swap that out and hopefully it's fixed.
3. Bundle up the phase and power wires so they don't drag on the ground.

Other stuff to come soon...

1. Once I have the Power Velocity 12 fet controller tested out and configured, I'll swap out it's IRF4110 fets for AOT290's and then I'll be able to crank the throttle...until then I'll ride it casually so I don't burn out the 2500 watt Grinfineon controller on my 7000 watt C80100.

2. This may or may not need tweaking...don't know yet until I ride around a little. The gearing is currently an estimation of what I think will be a good balance of torque and speed. I may go up or down a few teeth on the motor sprocket to get that squared away.

3. The LIPOs are a temporary solution. I have loads of 18650's. I have a spot welder now and want to make up a LION battery pack for the scooter. Depending on how it does on 48 volts, I may go to 60 volts. The controller is good for 90 volts...so the sky is more or less the limit. If I go above 60 volts, I will have to get a higher voltage DC-DC converter. It's only good to 60 volts.

Last edited by ElectricGod on Aug 28 2017 6:22pm, edited 1 time in total.

E-ScooterDude wrote:That is coming along beautifully. Hopefully you'll have some nice weather to test it out in.

Thanks...the weather has been great this past week. I've scooted everywhere that was local. I just came back from lunch with some friends when I came out of the restaurant, there were two people with monster bikes that were getting them unlocked. They had 750 watt bafang hubs on them...under powered for the size of the bike and I bet they paid $5000 each for them. LOL! I have nearly 10X that wattage and maybe $500 in my scooter.

Yeah, I tell people the performance of my scoot and they are amazed such a small thing can go that fast for that many miles. It's a ton of fun and I've noticed that the bicycle is getting quite the layer of dust.

Your $500 investment is an amazing bargain for your expected level of performance.

E-ScooterDude wrote:Yeah, I tell people the performance of my scoot and they are amazed such a small thing can go that fast for that many miles. It's a ton of fun and I've noticed that the bicycle is getting quite the layer of dust.

Your $500 investment is an amazing bargain for your expected level of performance.

I know...people think EV's are expensive...but when you built it yourself, they don't cost a fortune.

I got the brake cable replaced. The linear hall in my throttle was dead, so I soldered in a replacement. All good to go now. Since the grintech isn't the final controller for this scooter, I did a sloppy job of tieing up the wires. They are out of the way and don't drag on anything...so good enough for now. It's 12:20am right now and I finished it up around 11:30pm. Of course I had to go take it for a spin. Battery voltage held at 46 volts for the couple of miles I rode around. The grinfineon controller wont do more than 2000 watts no matter what. Looking at the watt meter was proof too. At WOT and pulling a hill the most I ever got was 46 amps. That works out to 2100 watts. Acceleration is pretty tepid. I'm sure the motor can pull lots harder, but it's starving for amps that the grintech simply wont deliver in it's current state. I didn't need to kick off to get rolling. The motor was getting enough juice to do that on it's own. It's about 45F outside so it's hard to say if things will warm up in hotter weather or not, but the controller stayed cold the whole time and the motor "warmed up" to maybe 70F. Even at 2000 watts it will pop wheelies, but not very good ones. You have to lean back and crank the throttle. No great surprise there...I'm short another 2000 watts or so. Top speed was pretty weak too...I topped out at 25.6mph. Yawn! Ah well...the better controller is sitting on my bench right now and the AOT290 mosfets are on the way to me. Soon I'll be pulling 4000 watts. I was curious about sagging under full load, but there was almost none...a volt at most at 46 amp draw. The brakes worked great. It's a far more dynamic ride than the blue scooter. I will have to get used to making much smaller steering changes. This thing will turn around in a 5 foot diameter circle. It feels super low to the ground...mostly because its deck is so much lower that the blue scooter. It takes turns pretty nicely, but I didn't try pushing my luck on its maiden ride. The lack of shocks in the back feel a little harsher since there is no bounce back there. I occasionally bounce up and down on my blue scooter. I tried the same thing on the Currie and it was like landing on squishy concrete...almost no movement at all. I'm guessing it weighs about 60 pounds at most. I can pick it up easily enough. I carried it down my front steps to my drive way with minimal effort. The head lights are dead on and so much brighter than the one light on the blue scooter. The orange battery box lights look great in the dark. The COB leds on the main down tube are ridiculously bright in the dark. They lit up everything around me on either side of the scooter. I glanced over my shoulder a few times to see how the tail lights were doing and everything about them was super bright too. I'm pretty happy over all and of course better acceleration and top speed is just around the corner.

I realized earlier today that I need to mount the kick stand. I've got a couple places that will do well for that.

For a first ride, I'm generally pleased. Everything works...that's a great start!

shortcircuit911 wrote:That thing looks pretty good man. Looks like my welds held up because you're still alive lol. I'm curious to see how it performs with the new controller.

LOL...the welds will hold until I get comfy and I'm tearing along doing 50...then they will break. Even if a weld gives out and cracks, it's in the center of the outer steering tube. Most likely I will notice the wobble in the forks or handle bars before it breaks through all the way. Thanks to you, I have more length in the down tube. I was concerned about how high I have the handlebars on their down tube. There's a fair bit of flexing at the clamp in the middle of the tube. I lowered them an inch.

At the handlebars, I have a cluster of wires all coming together into a 24 position terminal block. As long as it never gets wet, it's probably fine. There's 48 volts, 12 volts, 5 volts, throttle, brakes, lights, horn, temp, etc all going into that terminal block a little water in there would short who knows what together. I found a 24 pin IP68 connector on ebay that will replace this wiring cluster f-ck....errrr ummm short waiting to happen.

I couple of days ago I received the Power Velocity 12 fet controller. It comes with IRF4110 mosfets in it and I'm replacing them with AOT290's. The AOT290 are 500 watts each, a bit faster and have a lower Rds. In preparation for the mosfet replacement, I'm getting the controller ready to handle much more wattage. I'll also replace the existing shunts with beefier ones to. The blue package is the bluetooth module.

Last night I replaced the 14 awg power and phase wires with 10 awg. 10 Awg has 2.5X more cross sectional area than 14 awg. What 14 awg looks like compared to 10 awg. That grey wire is 14 awg.

Tonight I improved the heat spreader. Since I intend to run this controller at 4000 watts, the thin wall of the shell isn't going to transfer heat well enough. I added a piece of aluminum angle that will greatly increase the heat spreading surface area to the shell. I wanted to be sure the aluminum angle was held securely to the shell so I drilled 3 holes through the top of the shell to thread screws into the heat spreader and pull the spreader up tight to the shell.

Last edited by ElectricGod on Aug 28 2017 6:27pm, edited 1 time in total.

I have replaced the IRF4110's with AOT290's in the controller and tested it out. It's running fine on the bench on a LightningRods small block. Next up will be to mount it on the scooter and give it a spin.

I bench tested it right after replacing the mosfets.

And...the completely reassembled controller.

Last edited by ElectricGod on Aug 28 2017 6:31pm, edited 1 time in total.

Is there any reason you use the cable operated callipers, that's the caliper my brushless came with the pads were very small and only moved from the one side I swapped them for shimmano look a like hydraulics they are a direct swap near enough just needed a longer rear hose, With both pads moving it stops the disc warping so easy with both sides pressing firm, plus the meat on the pad is larger with choices of sintered pads etc.
This is proberly my favorite build of yours I like them small and punchy.

Looking at pictures of your wheels there looks to be plenty of clearance for hydraulics, I like them because they are easy to set up for no disc rub as both sides move away from the disc a slightly warped disc is no probs overall better feel.

Ianhill wrote:The controller is sweet, the angle alu is a good addition.

Is there any reason you use the cable operated callipers, that's the caliper my brushless came with the pads were very small and only moved from the one side I swapped them for shimmano look a like hydraulics they are a direct swap near enough just needed a longer rear hose, With both pads moving it stops the disc warping so easy with both sides pressing firm, plus the meat on the pad is larger with choices of sintered pads etc.
This is proberly my favorite build of yours I like them small and punchy.

Looking at pictures of your wheels there looks to be plenty of clearance for hydraulics, I like them because they are easy to set up for no disc rub as both sides move away from the disc a slightly warped disc is no probs overall better feel.

These brakes are mechanical and yeah I know they are limited. I may swap over to hydraulics later. Post your brakes please. I had these brakes so no cost for new parts. Same for the levers. They are set up to barely not rub and they don't warp the rotors when they clamp.

shortcircuit911 wrote:Clean work man, that thing is going to be a beast!

There's a thread on ES where someone replaced the 4110's in this controller with IRF3077's and claimed they were getting 4000 watts. The AOT290 is a 500 watt mosfet. The IRF3077 is a 370 watt mosfet. It may be the IRF3077 is a better choice since it has a lower Rds...2.8 micro ohms and 120 amps max while the AOT290 is 3.5 micro ohms and 140 amps max. The 3077 will generate less heat with it's lower Rds. Those maximum currents are at 10 volts so...not very useful. At 48 volts and higher the total wattage will matter more and the AOT290 has the IRF3077 beat in this regard. Also the AOT290 switches much faster than the 3077 which will help the higher Rds. We'll see...but I'm pretty damned sure that 4000 watts wont be a problem and maybe a good bit more too. That 4000 watts is in linear mode. In non-linear mode mosfets can handle more amperage/watts.

Last edited by ElectricGod on Apr 04 2017 7:30pm, edited 1 time in total.

Ianhill wrote:Clarks M2 front and rear set I used from amazon.
They share the same pads as shimmano m525 and are uk made so the box says.

I had them as they where the cheap decent set and serviceable, I'm sure you will find alot better in the US.

Im tempted to pop on a power velocity 12 fet it's a damn good bit of kit.

Upgrade the power and phase wires and the fets. I haven't had the chance to load test it yet, but I bet it will be nice. BTW...to get 10 awg wires through the board, I had to open up the holes a little and even then the wires were a tight fit. Phase and power transfers to the top of the board, but that's all low wattage and there are multiple other through holes that transfer through the board. It's not a problem. The large traces where all the current load is are on the bottom of the board and that's where the ends of the wires solder down. With the much larger wires, I bent over the ends in multiple directions while soldering them down. That will help spread current loading around a bit more.

Minor problem with the controller. The bluetooth module is defective. It all works great as long as you are connected via your phone, but if not, then the module goes crazy after a few minutes and deactivates the controller. Vadym at PowerVelocity is super responsive. I've been emailing him about updates to the phone app and other improvements. He usually responds back in a few minutes. Same for the bluetooth issue. I have replacement parts coming. He's had this problem with one other controller. It's just a bad batch of bluetooth modules.

I swapped out the BT module from my 18fet controller into the 12 fet controller. Anyway, it's all working now. Once it was all tested on my bench, I mounted it and got all the wiring zipped up and secured. I took it out for a ride, it's definately a lot stronger than before, but my current battery packs are not keeping up their end of the deal. They just can't deliver what the controller can take. I knew going into this that the battery pack was going to be inadequate. Anyway, she runs and pulls wheelies pretty easily now. I'll be upgrading to 16S from 12S. I don't know what I topped out at. I was going for more feel of acceleration and throttle response than anything else. I had regen set to maximum which meant deceleration was really strong. There was almost no coasting at all. I turned that down by 50%. The throttle at low RPMs is super jerky. The controller has some interesting settings in it. You can adjust phase current separate from acceleration power. It's kind of a throttle curve. Anyway, I turned that down by 30% in hopes that the throttle will be a bit more manageable. On my test ride, at low RPMs, there was no low speed maneuvering. You basically got on the throttle and take off. I'll take it out tomorrow and try it again with regen and throttle turned down a bit.

Last edited by ElectricGod on Aug 28 2017 6:31pm, edited 1 time in total.